1/*
2 * Copyright (C) 2005, 2006, 2007 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef JSRetainPtr_h
30#define JSRetainPtr_h
31
32#include <JavaScriptCore/JSStringRef.h>
33#include <algorithm>
34
35inline void JSRetain(JSStringRef string) { JSStringRetain(string); }
36inline void JSRelease(JSStringRef string) { JSStringRelease(string); }
37
38enum AdoptTag { Adopt };
39
40template <typename T> class JSRetainPtr {
41public:
42    JSRetainPtr() : m_ptr(0) {}
43    JSRetainPtr(T ptr) : m_ptr(ptr) { if (ptr) JSRetain(ptr); }
44
45    JSRetainPtr(AdoptTag, T ptr) : m_ptr(ptr) { }
46
47    JSRetainPtr(const JSRetainPtr& o) : m_ptr(o.m_ptr) { if (T ptr = m_ptr) JSRetain(ptr); }
48
49    ~JSRetainPtr() { if (T ptr = m_ptr) JSRelease(ptr); }
50
51    template <typename U> JSRetainPtr(const JSRetainPtr<U>& o) : m_ptr(o.get()) { if (T ptr = m_ptr) JSRetain(ptr); }
52
53    T get() const { return m_ptr; }
54
55    T releaseRef() { T tmp = m_ptr; m_ptr = 0; return tmp; }
56
57    T operator->() const { return m_ptr; }
58
59    bool operator!() const { return !m_ptr; }
60
61    // This conversion operator allows implicit conversion to bool but not to other integer types.
62    typedef T JSRetainPtr::*UnspecifiedBoolType;
63    operator UnspecifiedBoolType() const { return m_ptr ? &JSRetainPtr::m_ptr : 0; }
64
65    JSRetainPtr& operator=(const JSRetainPtr&);
66    template <typename U> JSRetainPtr& operator=(const JSRetainPtr<U>&);
67    JSRetainPtr& operator=(T);
68    template <typename U> JSRetainPtr& operator=(U*);
69
70    void adopt(T);
71
72    void swap(JSRetainPtr&);
73
74private:
75    T m_ptr;
76};
77
78template <typename T> inline JSRetainPtr<T>& JSRetainPtr<T>::operator=(const JSRetainPtr<T>& o)
79{
80    T optr = o.get();
81    if (optr)
82        JSRetain(optr);
83    T ptr = m_ptr;
84    m_ptr = optr;
85    if (ptr)
86        JSRelease(ptr);
87    return *this;
88}
89
90template <typename T> template <typename U> inline JSRetainPtr<T>& JSRetainPtr<T>::operator=(const JSRetainPtr<U>& o)
91{
92    T optr = o.get();
93    if (optr)
94        JSRetain(optr);
95    T ptr = m_ptr;
96    m_ptr = optr;
97    if (ptr)
98        JSRelease(ptr);
99    return *this;
100}
101
102template <typename T> inline JSRetainPtr<T>& JSRetainPtr<T>::operator=(T optr)
103{
104    if (optr)
105        JSRetain(optr);
106    T ptr = m_ptr;
107    m_ptr = optr;
108    if (ptr)
109        JSRelease(ptr);
110    return *this;
111}
112
113template <typename T> inline void JSRetainPtr<T>::adopt(T optr)
114{
115    T ptr = m_ptr;
116    m_ptr = optr;
117    if (ptr)
118        JSRelease(ptr);
119}
120
121template <typename T> template <typename U> inline JSRetainPtr<T>& JSRetainPtr<T>::operator=(U* optr)
122{
123    if (optr)
124        JSRetain(optr);
125    T ptr = m_ptr;
126    m_ptr = optr;
127    if (ptr)
128        JSRelease(ptr);
129    return *this;
130}
131
132template <class T> inline void JSRetainPtr<T>::swap(JSRetainPtr<T>& o)
133{
134    std::swap(m_ptr, o.m_ptr);
135}
136
137template <class T> inline void swap(JSRetainPtr<T>& a, JSRetainPtr<T>& b)
138{
139    a.swap(b);
140}
141
142template <typename T, typename U> inline bool operator==(const JSRetainPtr<T>& a, const JSRetainPtr<U>& b)
143{
144    return a.get() == b.get();
145}
146
147template <typename T, typename U> inline bool operator==(const JSRetainPtr<T>& a, U* b)
148{
149    return a.get() == b;
150}
151
152template <typename T, typename U> inline bool operator==(T* a, const JSRetainPtr<U>& b)
153{
154    return a == b.get();
155}
156
157template <typename T, typename U> inline bool operator!=(const JSRetainPtr<T>& a, const JSRetainPtr<U>& b)
158{
159    return a.get() != b.get();
160}
161
162template <typename T, typename U> inline bool operator!=(const JSRetainPtr<T>& a, U* b)
163{
164    return a.get() != b;
165}
166
167template <typename T, typename U> inline bool operator!=(T* a, const JSRetainPtr<U>& b)
168{
169    return a != b.get();
170}
171
172
173#endif // JSRetainPtr_h
174